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Revision 1.24 by root, Sun Aug 5 16:45:54 2007 UTC vs.
Revision 1.29 by root, Wed Apr 16 16:45:30 2008 UTC

24 $req->cancel; # cancel request if still in queue 24 $req->cancel; # cancel request if still in queue
25 25
26 my $grp = aio_group sub { print "all stats done\n" }; 26 my $grp = aio_group sub { print "all stats done\n" };
27 add $grp aio_stat "..." for ...; 27 add $grp aio_stat "..." for ...;
28 28
29 # AnyEvent integration 29 # AnyEvent integration (EV, Event, Glib, Tk, urxvt, pureperl...)
30 open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!"; 30 open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!";
31 my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb }); 31 my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb });
32
33 # EV integration
34 my $w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
32 35
33 # Event integration 36 # Event integration
34 Event->io (fd => IO::AIO::poll_fileno, 37 Event->io (fd => IO::AIO::poll_fileno,
35 poll => 'r', 38 poll => 'r',
36 cb => \&IO::AIO::poll_cb); 39 cb => \&IO::AIO::poll_cb);
258 } 261 }
259 }; 262 };
260 263
261 aio_close $fh, $callback->($status) 264 aio_close $fh, $callback->($status)
262 Asynchronously close a file and call the callback with the result 265 Asynchronously close a file and call the callback with the result
263 code. *WARNING:* although accepted, you should not pass in a perl 266 code.
264 filehandle here, as perl will likely close the file descriptor
265 another time when the filehandle is destroyed. Normally, you can
266 safely call perls "close" or just let filehandles go out of scope.
267 267
268 This is supposed to be a bug in the API, so that might change. It's 268 Unfortunately, you can't do this to perl. Perl *insists* very
269 therefore best to avoid this function. 269 strongly on closing the file descriptor associated with the
270 filehandle itself.
271
272 Therefore, "aio_close" will not close the filehandle - instead it
273 will use dup2 to overwrite the file descriptor with the write-end of
274 a pipe (the pipe fd will be created on demand and will be cached).
275
276 Or in other words: the file descriptor will be closed, but it will
277 not be free for reuse until the perl filehandle is closed.
270 278
271 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 279 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
272 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 280 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
273 Reads or writes $length bytes from the specified $fh and $offset 281 Reads or writes $length bytes from the specified $fh and $offset
274 into the scalar given by $data and offset $dataoffset and calls the 282 into the scalar given by $data and offset $dataoffset and calls the
275 callback without the actual number of bytes read (or -1 on error, 283 callback without the actual number of bytes read (or -1 on error,
276 just like the syscall). 284 just like the syscall).
277 285
278 If $offset is undefined, then the current file offset will be used 286 If $offset is undefined, then the current file descriptor offset
279 (and updated), otherwise the file offset will not be changed by 287 will be used (and updated), otherwise the file descriptor offset
280 these calls. 288 will not be changed by these calls.
281 289
282 If $length is undefined in "aio_write", use the remaining length of 290 If $length is undefined in "aio_write", use the remaining length of
283 $data. 291 $data.
284 292
285 If $dataoffset is less than zero, it will be counted from the end of 293 If $dataoffset is less than zero, it will be counted from the end of
521 Delete a directory tree starting (and including) $path, return the 529 Delete a directory tree starting (and including) $path, return the
522 status of the final "rmdir" only. This is a composite request that 530 status of the final "rmdir" only. This is a composite request that
523 uses "aio_scandir" to recurse into and rmdir directories, and unlink 531 uses "aio_scandir" to recurse into and rmdir directories, and unlink
524 everything else. 532 everything else.
525 533
534 aio_sync $callback->($status)
535 Asynchronously call sync and call the callback when finished.
536
526 aio_fsync $fh, $callback->($status) 537 aio_fsync $fh, $callback->($status)
527 Asynchronously call fsync on the given filehandle and call the 538 Asynchronously call fsync on the given filehandle and call the
528 callback with the fsync result code. 539 callback with the fsync result code.
529 540
530 aio_fdatasync $fh, $callback->($status) 541 aio_fdatasync $fh, $callback->($status)
531 Asynchronously call fdatasync on the given filehandle and call the 542 Asynchronously call fdatasync on the given filehandle and call the
532 callback with the fdatasync result code. 543 callback with the fdatasync result code.
533 544
534 If this call isn't available because your OS lacks it or it couldn't 545 If this call isn't available because your OS lacks it or it couldn't
535 be detected, it will be emulated by calling "fsync" instead. 546 be detected, it will be emulated by calling "fsync" instead.
547
548 aio_pathsync $path, $callback->($status)
549 This request tries to open, fsync and close the given path. This is
550 a composite request intended tosync directories after directory
551 operations (E.g. rename). This might not work on all operating
552 systems or have any specific effect, but usually it makes sure that
553 directory changes get written to disc. It works for anything that
554 can be opened for read-only, not just directories.
555
556 Passes 0 when everything went ok, and -1 on error.
536 557
537 aio_group $callback->(...) 558 aio_group $callback->(...)
538 This is a very special aio request: Instead of doing something, it 559 This is a very special aio request: Instead of doing something, it
539 is a container for other aio requests, which is useful if you want 560 is a container for other aio requests, which is useful if you want
540 to bundle many requests into a single, composite, request with a 561 to bundle many requests into a single, composite, request with a
622 }; 643 };
623 644
624 This makes it very easy to create composite requests (see the source of 645 This makes it very easy to create composite requests (see the source of
625 "aio_move" for an application) that work and feel like simple requests. 646 "aio_move" for an application) that work and feel like simple requests.
626 647
627 * The IO::AIO::GRP objects will be cleaned up during calls to 648 * The IO::AIO::GRP objects will be cleaned up during calls to
628 "IO::AIO::poll_cb", just like any other request. 649 "IO::AIO::poll_cb", just like any other request.
650
629 * They can be canceled like any other request. Canceling will cancel not 651 * They can be canceled like any other request. Canceling will cancel
630 only the request itself, but also all requests it contains. 652 not only the request itself, but also all requests it contains.
653
631 * They can also can also be added to other IO::AIO::GRP objects. 654 * They can also can also be added to other IO::AIO::GRP objects.
655
632 * You must not add requests to a group from within the group callback 656 * You must not add requests to a group from within the group callback
633 (or any later time). 657 (or any later time).
634 658
635 Their lifetime, simplified, looks like this: when they are empty, they 659 Their lifetime, simplified, looks like this: when they are empty, they
636 will finish very quickly. If they contain only requests that are in the 660 will finish very quickly. If they contain only requests that are in the
637 "done" state, they will also finish. Otherwise they will continue to 661 "done" state, they will also finish. Otherwise they will continue to
638 exist. 662 exist.
655 request itself. Useful when you queued a lot of events but got a 679 request itself. Useful when you queued a lot of events but got a
656 result early. 680 result early.
657 681
658 $grp->result (...) 682 $grp->result (...)
659 Set the result value(s) that will be passed to the group callback 683 Set the result value(s) that will be passed to the group callback
660 when all subrequests have finished and set thre groups errno to the 684 when all subrequests have finished and set the groups errno to the
661 current value of errno (just like calling "errno" without an error 685 current value of errno (just like calling "errno" without an error
662 number). By default, no argument will be passed and errno is zero. 686 number). By default, no argument will be passed and errno is zero.
663 687
664 $grp->errno ([$errno]) 688 $grp->errno ([$errno])
665 Sets the group errno value to $errno, or the current value of errno 689 Sets the group errno value to $errno, or the current value of errno
851 $oldmaxreqs = IO::AIO::max_outstanding $maxreqs 875 $oldmaxreqs = IO::AIO::max_outstanding $maxreqs
852 This is a very bad function to use in interactive programs because 876 This is a very bad function to use in interactive programs because
853 it blocks, and a bad way to reduce concurrency because it is 877 it blocks, and a bad way to reduce concurrency because it is
854 inexact: Better use an "aio_group" together with a feed callback. 878 inexact: Better use an "aio_group" together with a feed callback.
855 879
856 Sets the maximum number of outstanding requests to $nreqs. If you to 880 Sets the maximum number of outstanding requests to $nreqs. If you do
857 queue up more than this number of requests, the next call to the 881 queue up more than this number of requests, the next call to the
858 "poll_cb" (and "poll_some" and other functions calling "poll_cb") 882 "poll_cb" (and "poll_some" and other functions calling "poll_cb")
859 function will block until the limit is no longer exceeded. 883 function will block until the limit is no longer exceeded.
860 884
861 The default value is very large, so there is no practical limit on 885 The default value is very large, so there is no practical limit on
907 bytes of memory. In addition, stat requests need a stat buffer (possibly 931 bytes of memory. In addition, stat requests need a stat buffer (possibly
908 a few hundred bytes), readdir requires a result buffer and so on. Perl 932 a few hundred bytes), readdir requires a result buffer and so on. Perl
909 scalars and other data passed into aio requests will also be locked and 933 scalars and other data passed into aio requests will also be locked and
910 will consume memory till the request has entered the done state. 934 will consume memory till the request has entered the done state.
911 935
912 This is now awfully much, so queuing lots of requests is not usually a 936 This is not awfully much, so queuing lots of requests is not usually a
913 problem. 937 problem.
914 938
915 Per-thread usage: 939 Per-thread usage:
916 940
917 In the execution phase, some aio requests require more memory for 941 In the execution phase, some aio requests require more memory for

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